A radial arm saw has a flat horizontal table for holding the piece of wood stock which is to be cut. The table has a fence or guide that projects above the table and is used to align the wood stock relative to the saw blade. It is frequently desirable to cut the wood stock to an accurate length. Furthermore, it is frequently desirable to accurately cut plural pieces of wood stock to the same length. A stop apparatus for releasably attaching to the fence can be useful in achieving accurate cuts. The stop apparatus is used by locking it onto the fence in the appropriate position. The wood stock is positioned on the table so as to abut against the fence, with one end of the stock abutting against the stop apparatus. With the stock so positioned, the cut can be made. The stop apparatus can be released from the fence for repositioning.